Sparda

Sparda is a great demon, who is also known as "the legendary dark knight". Two thousand years ago, he "woke up to justice" and alone defeated Mundus and his legions. When sealing the netherworld, sensing his power had grown too strong, he intentionally seals himself and his own accursed power in as well. Later, he escaped his prison and quietly reigned the human world and continued to preserve harmony. Before his death, he resurfaced in the modern day and fell in love and married Eva, who gave birth to his twin sons, Dante and Vergil.

Physical Appearance & Personality
In his human form, Sparda looks exactly like his sons. His rebellious nature was that of Dante, while he also had the cold yet level headed personality of Vergil. His hair was swept back, long, silver and wavy, and he is always portrayed as wearing a purple or black jacket.

In his true form, Sparda was a human sized, humanoid demon, with four toed reptilian paws, a semi-reptilian hide, a pair of sweeping horns, a pair of hybrid feathered/bat wings and reptilian spines protruding from his back. His entire body appears to be made of grey armor with accents and overtones of red and purple among his very white flash, and features biological decorations, such as molten gold veins about his hands and arms, chest, shoulders and back, a diamond shaped red gem in the center of his chest, as well as skull-shaped gold knee and elbow guards.

Before Devil May Cry 3 Manga
Sparda was once one of Mundus's loyal generals. During his time in service, he was the mentor of the twin brothers Baul & Modeus, and he entrusted his teachings to Modeus. At some point he saw the tyranny and injustice of his master and rebelled, fighting to save humanity. Before his rebellion, he made a pact with his students to live true to their aspirations and to carry them out. He alone defeated the hellish host, before moving on to the Emperor of Darkness himself. Sparda defeated Mundus, sealing him into a marble vault, and what was left of Mundus's armies retreated back into the demon world. In order to close the gateway, Sparda used his own blood, along with the blood of a human priestess, in conjunction with his sword and a mystical amulet. He poured his demonic energy into his beloved sword to close the door between realms, the Temen-ni-gru, though this also robbed him of the lion's share of his abilities. As an added measure, he also imprisoned within the tower its gatekeepers, Cerberus, Agni & Rudra, Nevan, Beowulf and Leviathan, and took the names of the Seven Sins in order to imprison them and set them as seals keeping the Temen-ni-gru underground. In Devil May Cry 4 it is revealed that he sealed another path to hell in Fortuna using the Yamato. Sparda's activities over the next two thousand years are shrouded in legend, though it is understood that for a time after defeating Mundus, he ruled over the humans before eventually vanishing. Sparda later appeared in the twentieth century where he met and fell in love with a human woman named Eva, who bore him twin sons.

Devil May Cry 3
Arkham uses the Sons of Sparda to open the gate to the Netherworld, in order to obtain the Force Edge and thus obtaining the powers of Sparda himself. While he is able to use it to temporarily take on Sparda's form, he is unable to truly resonate with it and soon transforms into a hideous mass of demonic ectoplasm.

Devil May Cry
Sparda is referenced frequently throughout the game. At the start of the battle with Mundus, Dante finally awakens the true powers of Sparda's sword, and assumes Sparda's form as a new Devil Trigger. In this form, Dante can fly, shoot fireballs from his fists, and summon a spectral dragon. While fighting on the ground during the second part of the boss battle, Dante can also charge the fireballs, and the range of his sword is greatly extended.

Devil May Cry: The Animated Series
It is revealed that Sparda once had two apprentices, the twin brothers Baul & Modeus.

Devil May Cry 4
The Order of the Sword is a group of demon hunters that worship Sparda. Nero, the main protagonist of Devil May Cry 4 is blood linked to Sparda, and referenced multiple times in Sparda's rebellious nature.

The demon Berial implies that he encountered Sparda when he came to the Human World two millennia prior, telling Nero, "You are just like he was..."

The readings of His Holiness reveal that Sparda is not just a devil: he has emotions and can love, and in this lies his strength. This actually explains why all of those who assert to gain his power fail, as no one of them did what they did because of love for humans.

Devil May Cry 2
During Dante's first meeting with Matier, the old woman reveals that Sparda once fought alongside the Vie de Marli clan. Dante mentions that Sparda once crossed into the Demon world and returned. It is also revealed that Sparda once fought against Argosax and Bolverk.

Marvel vs. Capcom 3: Fate of Two Worlds
Sparda is a downloadable costume for Dante, and his own devil form replaces Dante's while in Devil Trigger.

Powers and Abilities
The exact extent of Sparda's powers remains unknown; but it is shown that his powers surpassed even the "Prince of Darkness" himself. Though it is to be seen that his powers stem from a heat related aspect, the exact nature of his powers are uncertain as his devil form appears to be partly corporeal-scales and flesh-and partly ghostly-as if made from smoke. As in Dante the abilities and utilization of fire and electricity seem to be among his abilities. But his power seems to transcend all reality. Arkham himself likened obtaining Sparda's power to becoming a god. In Devil May Cry 3, Dante was unable to defeat Arkham, who wielded the Sparda sword (and thus Sparda's powers) at the time, until Vergil shows up. However, it should be noted that Griffon in the first Devil May Cry admonished, after being defeated for the final time, that "[Dante's] are definitely the powers of Sparda. No, even more so.". Also, Nero was able to defeat Sanctus, who wielded Sparda and was connected to the powers of The Savior. It is suggested in Devil May Cry 4 that Sparda acquired the true extent of his power by embracing humanity, which would explain why the demons who attempt to augment their own power with Sparda's are unable to defeat the sons of Sparda.

Weapons
Sparda used both Yamato and Sparda, before putting the latter to sleep by draining his power into it, turning it into the Force Edge. He also used the Luce & Ombra, his own hand made pistols. Also, in Devil May Cry 3 it is stated that Rebellion is a memento from Sparda.

Trivia

 * In the Devil May Cry 3 manga, the Seven Sins state that Sparda was once very rebellious, and that Dante's attitude resembles Sparda.
 * In Devil May Cry and Devil May Cry 3, Dante can obtain the "Legendary Dark Knight" costume by clearing Hard mode. In Devil May Cry, this seems to actually be Sparda himself, as Dante's Ebony & Ivory are replaced with Sparda's Luce & Ombra. The sword Yamato is added to his arsenal, but players can still use Alastor. Yamato is basically a clone of Alastor, but when Sparda Devil Triggers, Yamato turns into the sword Sparda. Dante's DT and shadow are that of Sparda's devil form, no matter the equipped Devil Arm, though his abilities still depend on that Devil Arm.
 * In Devil May Cry 3, Dante's "DMC1 Dante" and "Coatless DMC1 Dante" costumes assume the form of Sparda while in Devil Trigger, possibly reference to how Dante, in the end of DMC1, takes the Force Edge and uses Sparda's Devil Form to defeat Mundus.
 * Sparda's coat and general dress being purple appears to be a combination of Vergil and Dante's trademark colors, or rather their red and blue being a split. His hair also seems to be a middle ground between Dante and Vergil, slicked back but not as spiky as Vergil's.
 * In Devil May Cry 4, Nero's costume mimics the purple and red color scheme of Sparda's outfit, further illustrating the connection between the two.